JP2003262670A - Apparatus for monitoring radio wave - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a monitoring apparatus for radio waves which overcomes the problem of a conventional radio wave monitoring apparatus for monitoring a target wave, such as a radio wave used in unauthorized manner needs much time and induces mistakes of inputs since it manually removes unwanted radio waves such as radio waves used in unauthorized manner from received signals and automatically screens the target wave from the received signals. <P>SOLUTION: The received signals are limited by one or a plurality of conditions of frequency value, band width, appearance time width and a modulation system. The signals corresponding to the limiting conditions are received by an upper apparatus and other signal components as the unwanted waves are not received. The radio wave monitoring apparatus for automatically screening the target wave from the received signals is obtained. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio wave monitoring device for extracting a target signal from received signals and notifying the extracted target signal to a host device.

[0002]

2. Description of the Related Art For example, in a radio wave monitoring device for monitoring illegal radio waves used in a frequency band which is not originally permitted, conventionally, unnecessary radio waves (in this case, radio waves legally used) In order not to notify the host device, parameters such as broadcast wave whose frequency is known in advance are manually input and set from the host device such as the display unit, and even if unnecessary radio waves are detected. Not to notify the host device.

However, unnecessary radio waves that do not need to be notified to the host device have unknown timings that appear in advance, such as intermittent waves such as control signals transmitted from mobile communication base stations, and other frequencies. It also includes continuously changing modulated waves. For example, when the frequency band is HF, there are nearly 1000 waves at night when the number of used radio waves increases. Therefore, it is necessary to manually mask these radio waves, which requires a large amount of time and burden for input, and also causes a problem of erroneous input.

In the microwave region only, there is a microwave detecting device disclosed in Japanese Patent Laid-Open No. 10-307180, for example, as a signal detecting device for detecting a target signal even if there is an unnecessary radio wave. FIG. 13 shows Japanese Patent Laid-Open No. 10-307.
It is a block diagram which shows the microwave detection device mounted in the vehicle for detecting the microwave emitted from the radar-type speed measuring device shown by the 180th publication. In the figure, 1 is a horn antenna, 2 is a local oscillator, 3 is a mixer, 4 is an intermediate frequency amplifier circuit, 5 is a wave detector, 6 is a signal identification circuit, and 7
Is an alarm circuit, 8 is an alarm device, 9 is a control voltage generator, 10 is a microcomputer, 11 is a memory, 12 is an AD converter, 15
Is a forced jamming radio wave detection switch, and 16 is a reset switch.

As shown in the figure, the input of the horn antenna 1 and the output of the local oscillator 2 are frequency-mixed by the mixer 3. The intermediate frequency signal thus obtained is band-amplified through the intermediate frequency amplifier (BPF + AMP) 4 in the next stage and then input to the wave detector 5. Then, based on the detection signal output from the detector 5, the signal discrimination circuit 6 determines whether or not the target microwave is present. If the microwave is present, the detection signal is sent to the alarm circuit 7 Send to. When the alarm circuit 7 receives the detection signal, the alarm device 8
To notify you. The alarm device 8 may be a buzzer, an alarm sound or the like or a lamp or the like.

The local oscillator 2 is controlled by a sawtooth wave or a triangular wave generated from the control voltage generator 9, and the frequency of the output of the local oscillator 2 that mixes the frequency with the received signal is periodically within the received signal band. To sweep. Therefore, FIG.
When the sweep control voltage changes as shown in (a), a large peak appears in the output of the detector 5 when the microwave of the corresponding frequency exists as shown in (b) of the figure, and in other regions. White noise appears. Therefore, as the signal discriminating circuit 7, for example, by using a comparator having a threshold voltage Th that can be discriminated from white noise as a reference voltage, as shown in FIG. The pulse can be turned on only when the above microwaves are received. That is, when the pulse is turned on, the above-mentioned detection signal is obtained.
When the alarm circuit 7 receives the pulse (ON), the alarm circuit 8 outputs the alarm device 8 for a predetermined time (at least one sweep time or more).
To operate.

The above-described structure is a superheterodyne type microwave detector generally used. Here, in the conventional example, the microcomputer 10 as the jamming radio wave detecting means is used.
Is connected to the output of the signal identification circuit 6 so that the detection signal can be obtained. Then, the microcomputer 10 monitors the appearance state of the detection signal, and when it determines that it is an interfering radio wave, it stores information on the interfering radio wave in the memory 11.

Further, the microcomputer 10 invalidates the detection signal when the detection signal is an interfering radio wave, and prevents the alarm circuit 7 and / or the alarm device 8 from operating depending on the interfering radio wave. That is, based on the information stored in the memory 11, it is determined whether the detection signal is an interfering radio wave,
The alarm is not output when it is determined that the radio wave is the interference.

The detection of the interfering wave is performed as follows. The microwave to be detected is detected only for a certain period, but when the vehicle moves, the microwave disappears when it passes through the installation position of the radar type speed measuring device which is the source of the microwave. On the other hand, in the case of an interfering radio wave, if it is an electromagnetic wave emitted from an electronic device or the like existing in the vehicle compartment, it is constantly generated while the electronic device or the like is used regardless of the movement of the vehicle. Therefore, when signals of the same frequency are continuously received for a certain period of time or more, it is determined to be an interfering radio wave, and the information is stored in the memory 11. As a result, the memory 1
When the same signal as the interference radio wave stored in 1 is received, it is detected and the alarm circuit 7 is not activated.

Japanese Unexamined Patent Application Publication No. 10-307180 is configured as described above, and as a radio wave monitoring device, it is an illegal radio wave whether it is an intermittent radio wave or an unnecessary radio wave, or a continuous wave for communication. In some cases, the target wave may be the target wave, and the target wave is not automatically selected according to the radio wave specifications.

[0011]

The radio wave monitoring apparatus according to the present invention has been made to solve the above-mentioned problems, and the received signal is converted into frequency value, bandwidth, appearance time width,
The target wave is automatically detected from the received signal by limiting it to any one or more of the modulation methods, notifying the host device of the signal that meets the limiting condition, and not notifying other signal components as unnecessary waves. The purpose of the present invention is to obtain a radio wave monitoring device for selective selection.

[0012]

A radio wave monitoring apparatus according to the present invention includes a receiving apparatus for receiving a radio signal and converting it into an intermediate frequency, and an AD for converting a received signal of the intermediate frequency into an AD.
A converter, a fast Fourier transformer that sequentially performs a fast Fourier transform on the AD-converted received signal to calculate a frequency distribution, and any one or a plurality of conditions of a frequency value, a bandwidth, and an appearance time width of a target wave. Input device for inputting, the input frequency peak position, any one or more of the frequency peak bandwidth, the appearance time width, and the frequency distribution of the received signal corresponding to the condition. It is provided with a signal extractor which determines whether or not any one or more conditions of the peak frequency value, the bandwidth, and the appearance time width are matched, and notifies the matched peak to the higher-level device.

Further, the signal extractor determines that a peak exists when a signal level higher than a preset value is measured.

Further, a receiver for receiving a radio signal and converting it to an intermediate frequency, an AD converter for AD-converting the received signal of the intermediate frequency, and the AD-converted received signal into an in-phase component and a quadrature component. Distribution means for distributing, fast Fourier transform means for calculating the frequency distribution and the phase at each frequency value by performing fast Fourier transform on the in-phase component and quadrature component respectively, and the frequency value, bandwidth, appearance of the target wave An input device for inputting one or more conditions of time width and modulation method, and the input frequency value,
Bandwidth, appearance time width, any one or more conditions of the modulation method, and frequency value included in the frequency distribution of the received signal, bandwidth, appearance time width, any one or more conditions of the modulation method It is provided with a signal extractor that determines whether or not they match and notifies the upper device of the matched peak.

Further, the signal extractor comprises frequency distribution synthesizing means for synthesizing a frequency distribution from a preset modulation method and modulation rate, scans the frequency band of the received signal, and outputs the synthesized frequency distribution waveform. It is determined whether or not there is a matching peak, and the matching peak is notified to the host device.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. The radio wave monitoring apparatus according to the first embodiment of the present invention limits a signal component included in a received signal according to conditions of a frequency value, a bandwidth, and an appearance time width that are input in advance from a higher-level device such as a display,
The upper component is notified of a signal component that matches the limiting condition as the target wave.

FIG. 1 is a block diagram showing the configuration of the radio wave monitoring apparatus according to the first embodiment. In the figure, 1 is an antenna, 2 is a high frequency amplifier, 3 is a mixer, 4 is an intermediate frequency amplifier, 100 is a high frequency amplifier 2, a mixer 3,
A receiver including the intermediate frequency amplifier 4, 200 is an unnecessary wave removing device, 201 is an AD converter, 202 is a memory, 203
Is a signal processor, 204 is a control device, and 300 is a higher-level device such as a display and an input device.

Next, the operation will be described. Antenna 1
The radio wave received by is converted from a radio frequency to an intermediate frequency via the high frequency amplifier 2, the mixer 3 and the intermediate frequency amplifier 4, and the intermediate frequency signal is converted into an unnecessary wave removing device 2
00 is input. In the unnecessary wave removing device 200, the radio wave specifications of the target wave are input in advance from the host device.
First, the AD converter 201 converts an analog signal into a digital signal, and the memory 202 stores the sequentially sampled digital signals. Memory 20
The digital signal stored in 2 is input to the signal processing device 203, subjected to a fast Fourier transform process, and the processing result is compared with the radio wave data of the target wave input from the above-mentioned host device in advance to extract and control the signal. The device 204 determines the target wave and the unwanted wave, and only the one determined to be the target wave is notified to the higher-level device 300.

Here, the signal processing of the signal processing device 203 will be described in detail. FIG. 2 is a block diagram showing a detailed configuration of the unnecessary wave removing device 200. Reference numeral 250 is a down converter inside the signal processor 203, 251 is a filter for removing unnecessary high frequency components, 252 is a fast Fourier transformer, 253 is a signal extractor, and 254 is a memory.

Next, the operation of the signal processing device 203 will be described. The digital signal input from the memory 202 to the signal processing device 203 is band-reduced from the intermediate frequency to the base band by the down converter 250, unnecessary high frequencies are removed by the filter 251, and the fast Fourier transform is performed by the fast Fourier transformer 252. After the processing, the frequency spectrum is obtained.

FIG. 3 is a diagram showing a frequency spectrum after the received signal is subjected to the fast Fourier transform processing by the fast Fourier transformer 252. FIG. 3A is a frequency spectrum obtained by the fast Fourier transform at time T1. (B) is a frequency spectrum by the fast Fourier transform at time T2. (C) is a frequency spectrum by the fast Fourier transform at time Tn.

In the case of the example of FIG. 3, there are two signals. Usually, when the fast Fourier transform is performed, the bandwidth for performing the fast Fourier transform and the calculated discrete frequency points determine the number of band divisions and the frequency width of each discrete frequency. The signal level is compared for each point of this discrete frequency, and the discrete frequency value having a peak is calculated.

First, at time T1, as shown in FIG. 3A, the signal levels are compared from the lower frequency value,
The signal peak is recorded before the signal level becomes low. That is, in this case, peaks 50 and 51 exist in the discrete frequency values of f4 and f7 in the figure. Next, time T
At 2, the signal levels are compared in order from the lowest frequency value of the frequency spectrum shown in FIG. 3B, as at time T1. Although the peak 50 exists, the peak 51 existing at the time T1 disappears. Hereinafter, the same processing is repeated and stored in the memory 254. Then, as shown in FIG. 3C, the peak 50 at the time Tn exists at the third discrete frequency value, while the peak 51 exists again.

Next, based on the stored data, the signal identity and the bandwidth are determined. For example, when the discrete frequency value having a peak is stored in the memory based on FIG. 3 as shown in FIG. 4, the type of the signal is determined based on the time and the presence / absence of the discrete frequency value having the peak. . For example, if the frequency value is almost constant and exists continuously, it is a continuous wave, if the peak fluctuates with time in a constant frequency band, it is a modulated wave. Judge as an intermittent wave. In the case of FIG.
It is determined that the peak existing at the frequency f4 is a continuous wave and the peak existing at the frequency f7 is an intermittent wave.

Here, for example, the host device 30 is previously
The frequency value from 0 to the peak of the target wave is f4, and the bandwidth is f2
If a continuous wave of ~ f5 is set, peak 5
0 defines the frequency bandwidth in which the signal level drops by 3 dB from the frequency peak as shown in FIG. 3C as the frequency bandwidth of the signal, and the frequency value at which this peak exists, its bandwidth, and the appearance time are measured. If they match, this signal is notified to the higher-level device as the target wave, and other peaks 5
Regarding 1, the upper-level device is not notified as an unnecessary signal.

Further, if the specifications of the target wave from the host device are
When a discrete wave existing in the bandwidth A of FIG. 3C from the discrete frequency value of f5 is used, the peak 50 does not match the condition of the target wave, and therefore, as in the case of the peak 51, the peak 50 is regarded as an unnecessary signal. No notification is sent to the device.

As described above, in the first embodiment, in the radio wave monitoring device, the condition of the target wave input from the host device is compared with the time change of the frequency distribution of the received signal, and the condition of the target wave is met. If not, it is not necessary to manually remove various unnecessary radio waves, as it is not notified to the upper device as unnecessary signals in other cases. Obtain a radio wave monitoring device that automatically selects unnecessary waves and target waves according to the original.

Embodiment 2. In the first embodiment, the signal extractor 253 in the unnecessary signal removing unit 200 compares the signal levels for each frequency, but in the second embodiment, the preset threshold value is compared with the signal level.
If it is larger than the threshold value, 1 is output at the frequency value, and if it is smaller than the threshold value, 0 is output at the frequency value to perform binarization. by this,
The amount of memory used in the signal extractor 253 can be reduced, and the processing load can be reduced.

The device configuration of the second embodiment is the same as the device configuration of the first embodiment shown in FIGS. 1 and 2, but when a signal is extracted by the signal extractor 253, a constant threshold value is set for the signal level. A signal is extracted by providing the threshold value and comparing the signal level with the threshold value.

The bandwidth of the signal is determined from the distribution state of the frequencies showing the signal level equal to or higher than a predetermined threshold value set in advance. FIG. 4 shows the processing contents of signal extraction according to the second embodiment. 5A, 5B, and 5C are times T1 and T1, respectively.
It is a figure showing the frequency component of the signal in T2 and TN. In each figure, A represents a threshold value for signal extraction. At time T1, the frequency f2 as shown in FIG.
Since a signal level equal to or higher than the threshold value is observed at ~ f4 and f7, the signal distribution at that frequency is set to 1 and the other values are set to 0 and stored in the memory 254, as shown in FIG. 6A. At time T2, the peaks at frequencies f2 to f4 continuously exist as shown in FIG. 5B, but the peak at f7 disappears. Therefore, time T2
The result of the frequency analysis in is stored in the memory 254 as shown in FIG. This operation is performed for each sampling time. At time TN, as shown in FIG. 5C, the peaks at the frequencies f2 to f4 and the peak at the frequency f7 or more are present again. )
Is stored in the memory 254 as follows.

From the frequency analysis results stored in the memory 254 as described above, the appearance time and the disappearance time of the signal are measured, and the bandwidth, appearance time, time interval, etc. of the target wave previously input from the host device 300 are measured. It is determined whether the specifications match, and only if they match, the data is output to the higher-level device 300.

As described above, in the second embodiment, a threshold value is set in advance at the time of signal extraction, and if the signal level is equal to or higher than the threshold value, the signal exists, and the frequency distribution of the signal is obtained. The memory usage of the signal extractor is smaller than that in the first embodiment, and the processing load can be reduced.

Embodiment 3. In the third embodiment, the received signal is distributed to I and Q signals, the phase at each time is calculated from the signal, the modulation method is analyzed from the phase change, and the target wave is extracted.

FIG. 6 is a block diagram showing the configuration of the signal processing unit 200a of the radio wave monitoring apparatus according to the third embodiment.
The same components as those in FIG. 2 are designated by the same reference numerals. Reference numeral 255 denotes a distributor for distributing the reception signal band-limited by the filter 251 into an in-phase component (I component) and a quadrature component (Q component), and 252.
a is a fast Fourier transform means for fast Fourier transforming the I component of the received signal, 252b is fast Fourier transform means for fast Fourier transform of the Q component of the received signal, and 253a is the function of the signal extractor 253 of the first or second embodiment. In addition to,
It includes a phase difference detecting means 256 for detecting the phase by comparing the I and Q components of the received signal and detecting the phase difference between the respective times.

Next, the operation will be described. Signal processing unit 2
The received signal of the intermediate frequency input to 00a is converted into a digital signal by the AD converter 201, and the signal processor 203
Entered in. In the signal processor 203, the frequency is converted from the intermediate frequency to the base band by the down converter 250, the band of the unnecessary frequency band is limited by the filter 251, and the result is input to the distributor 255. Distributor 25
5, the received signal is divided into an I component and a Q component orthogonal thereto, and fast Fourier transform means 252a, 252a and 2F, respectively.
The fast Fourier transform is performed at 52b and the signal components Ae ^{j θ} are calculated for each frequency by comparing them. Here, A is the amplitude and θ is the phase. The frequency distribution is obtained from the calculated signal component, and the signal extractor 253a
Entered in. In the signal extractor 253a, in addition to the analysis of the peak frequency value, the peak bandwidth, and the appearance time width, as in the first and second embodiments, the phase difference detection unit 256 detects the phase difference at each time. .

For example, PSK (Phase Shift)
Keying) is a modulation method of transmitting information by phase difference, but unless the reference signal for phase identification is also transmitted, the receiving side does not know which phase is 0 radian (0 °). Therefore, DPSK (Deferen), which is a type of PSK,
Tial Phase Shift Keying) adopts a method of interpreting the phase of a sine wave transmitted immediately before the current one as 0 ° (reference) each time and discriminating the phase. For example, in 4-phase DPSK, + π / 2, 0, +3
The phase difference of either π / 2 or + π is taken. Therefore, when the higher-level device 300 sets the control unit 204 to set the modulation method to 4-phase DPSK, the fast Fourier transform device 2
Signal extractor 2 to which the calculation results of 52a and 252b are input
In 53, as shown in FIG. 7, the phase θ calculated at each frequency as described above is compared for each time, and the phase difference for each time is always + π / 2, 0, + 3π / 2,
Find a peak that is either + π.

FIG. 7 is a diagram showing the frequency distribution of the I component of the received signal, and FIG. 8 is a diagram showing the frequency distribution of the Q component of the received signal. 7A shows a time T1, FIG. 7B shows a time T2 which is the sampling timing next to the time T1, and FIG. 7C shows a frequency distribution of the I component of the received signal at the time TN. Further, FIG. 8A shows a certain time T1, FIG. 8B shows a time T2 which is the sampling timing next to the time T1,
FIG. 8C shows the frequency distribution of the Q component of the received signal at time TN. At time T1, the signal extractor 253 detects the phase by comparing the signal component of the frequency f4 from the I component to the peak 52a, the signal component of f7 from the peak 53b, and the Q component from the peak 52b and the peak 53b. Next, the peak phase is detected from the I and Q components at the frequencies f4 and f7 at time T2, and the phase difference between time T1 and time T2 is calculated. This operation is performed every time, and the phase difference is calculated. FIG. 9 shows the phase θ of the calculated signal component at each discrete frequency at each time T1, T2, ... TN. In the 4-phase DPSK, the phase difference corresponding to bits 00, 01, 10, 11 is assigned, for example, + π / 2, 0, + 3π / 2, + π, etc., but in the example of FIGS.
Since there is no phase change even when 2a and 52b are compared, the peak 52 is not notified to the host device 300. On the other hand, for the peak 53, the phase difference at each time is + π /
If the value is any one of 2, 0, + 3π / 2, and + π, the peak 53 is notified to the host device 300. Figure 7
And in FIG. 8, the high frequency side of f8 is not shown,
As a matter of course, when a signal in which the phase difference at each time has a value of + π / 2, 0, + 3π / 2, or + π on the higher frequency side than f8 is found, the signal component is detected. Is notified to the host device 300.

At that time, if the frequency band in which the target wave exists, the appearance time width, etc. are further specified by the higher-level device 300, the target wave can be extracted more efficiently by analyzing them together with the phase change. be able to.

That is, by analyzing the detected phase difference together with the frequency value of the peak, the bandwidth, and the appearance time width, the modulation method can be identified and the target wave can be extracted more accurately. For example, in analog modulation, AM (Amplitu)
de Modulation) and FM (Frequen)
Cy Modulation), or digital modulation, ASK (Amplitude Shift Key)
ing), PSK (Phase Shift Keyi)
ng), FSK (Frequency Shift K)
eyeing), QAM (Quadrature Amp)
By identifying a modulation method such as a light modulation, the types of received waves such as AM, FM broadcast waves, digital radio waves, voice signals and data signals are known, and it is easy to identify whether or not the waves are target waves.

As described above, in the third embodiment, the received signal is divided into I and Q components, the phase difference between each time is detected from the phase at each time from the I and Q components, and this phase difference is detected. However, it is possible to more accurately extract only the target signal by determining whether or not it matches the phase difference provided by the higher-level device by the preset modulation method.

Fourth Embodiment In the third embodiment, the received signal is divided into I and Q components, the frequency distributions of the I and Q components are compared to detect the phase, and the modulation method is identified from the phase difference at each sampling time. Although the radio wave monitoring device that notifies only the signal that matches the wave modulation method to the higher-level device is shown, in the fourth embodiment, the waveform of the frequency distribution is synthesized from the modulation method and the modulation speed set in the higher-level device, An explanation will be given of a radio wave monitoring device which compares the synthesized frequency distribution with the frequency distribution of the actual received signal and extracts only the signals having the same frequency distribution.

FIG. 10 is a block diagram showing the configuration of the radio wave extractor in the radio wave monitoring apparatus according to the fourth embodiment. The same components as those in FIG. 6 of the third embodiment described above are designated by the same reference numerals. Reference numeral 261 is a waveform synthesizing means in the control unit 204.

Next, the operation will be described. As in the third embodiment, the received signal is divided into I and Q components, the fast Fourier transform is performed to obtain the frequency distribution, and the frequencies are compared to detect the phase. Here, in the fourth embodiment, the waveform synthesizing means 25 incorporated in the signal extractor 253 is selected from the modulation scheme and the modulation speed set by the higher-level device 300.
The frequency distribution waveform is synthesized by 7 and the synthesized waveform is sequentially moved from the low frequency to the high frequency or from the high frequency to the low frequency at each time to scan whether the waveforms match.

FIG. 11 shows a method of scanning an objective wave according to the fourth embodiment. For example, the modulation method of the target wave is FSK,
And when the modulation rate is set to an appropriate value as the modulation rate of, for example, 2400 baud (the baud rate is a scale indicating how many times the signal changes in one second) from the higher-level device 300, the waveform synthesizing means 257 in the control unit 204 is performed. Then, the frequency waveforms of FSK are combined, and the combined peak is sequentially scanned from the low frequency side or the high frequency side, and it is scanned whether there is a matching waveform. At that time, FSK is 2 corresponding to 0 and 1 respectively.
Since it is a modulation method in which transmission is performed using one frequency, a peak appears in one of the two frequencies at fixed time intervals according to the modulation speed, and when the frequency distribution at each time is integrated, a composite frequency distribution 60 is obtained. A frequency distribution with two peaks is obtained. Further, if the modulation speed is high, the peak bandwidth is widened, and conversely, if the modulation speed is low, the peak bandwidth is narrowed accordingly. Therefore, in the fourth embodiment, the frequency distributions are integrated for a fixed time, the integrated frequency distribution is compared with the frequency distribution 60 synthesized by the waveform synthesizing means 257, and the matching peaks are scanned.

As a result of the scanning, when the peak 54 having the same frequency distribution is detected, the peak 54 is notified to the host device 300 as the target wave. As the waveform synthesizing means 257, an existing spectrum analyzer or the like is used as the signal extractor 2.
It may be used by incorporating it in 53.

Further, by setting the frequency value, bandwidth, appearance time width and the like of the target wave from the host device as in the first, second, and third embodiments and limiting the scanning range, more efficient operation is achieved. Good radio monitoring can be done.

In the above example, the modulation method of the target wave is FSK.
However, the modulation method used by the waveform synthesizing means 257 is not limited to FSK.

Further, in addition to the fourth embodiment, the antenna refers to an omnidirectional antenna in any of the above first, second, and third embodiments, but it may be applied to a directional array antenna or the like. FIG. 12 shows a configuration diagram of an array antenna using a plurality of radio wave monitoring devices of the present invention. By thus configuring the array antenna using a plurality of radio wave monitoring devices of the present invention, the arrival direction of the received radio wave can be limited, and more efficient radio wave monitoring can be performed. This is applicable to the radio wave monitoring devices of the first, second, and third embodiments as well as the fourth embodiment.

As described above, in the fourth embodiment, the waveform synthesizing means 257 incorporated in the signal extractor 253 synthesizes the frequency distribution waveforms in accordance with the modulation method and the modulation speed set by the host device, and the synthesized waveforms are obtained. Since it is scanned whether or not it matches the frequency waveform accumulated for a certain period of time, only the target signal can be extracted more accurately.

[0050]

As described above, the radio wave monitoring apparatus according to the present invention includes a receiving apparatus for receiving a radio signal and converting it to an intermediate frequency, and an AD for converting a received signal of the intermediate frequency to AD.
A converter, a fast Fourier transformer that sequentially performs a fast Fourier transform on the AD-converted received signal to calculate a frequency distribution, and any one or a plurality of conditions of a frequency value, a bandwidth, and an appearance time width of a target wave. Input device for inputting, the input frequency peak position, any one or more of the frequency peak bandwidth, the appearance time width, and the frequency distribution of the received signal corresponding to the condition. The frequency value of the peak, the bandwidth, to determine whether it matches any one or more conditions of the appearance time width, and a signal extractor for notifying the matched peak to the host device, so from the received signal The target wave can be automatically extracted.

Since the signal extractor determines that a peak exists when a signal level higher than a preset value is measured, the amount of memory used in the signal extractor can be reduced. is there.

Further, a receiving device for receiving a radio signal and converting it to an intermediate frequency, an AD converter for AD-converting the received signal of the intermediate frequency, and the AD-converted received signal into an in-phase component and a quadrature component. Distribution means for distributing, fast Fourier transform means for calculating the frequency distribution and the phase at each frequency value by performing fast Fourier transform on the in-phase component and quadrature component respectively, and the frequency value, bandwidth, appearance of the target wave An input device for inputting one or more conditions of time width and modulation method, and the input frequency value,
Bandwidth, appearance time width, any one or more conditions of the modulation method, and frequency value included in the frequency distribution of the received signal, bandwidth, appearance time width, any one or more conditions of the modulation method The target wave can be automatically extracted from the received signal because it is provided with a signal extractor that determines whether or not they match and notifies the upper device of the matched peak.

Further, the signal extractor comprises frequency distribution synthesizing means for synthesizing frequency distributions from preset modulation methods and modulation speeds, and scans the frequency band of the received signal to obtain the synthesized frequency distribution waveforms. It is possible to automatically extract the target wave more accurately from the received signal because it is determined whether there is a matching peak and the matching peak is notified to the host device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a radio wave monitoring device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an unnecessary wave removing device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a method of extracting an objective wave according to the first embodiment of the present invention. (A) The frequency distribution of the received signal at time T1. (B) Frequency distribution of the received signal at time T2. (C) Frequency distribution of the received signal at time TN.

FIG. 4 is data stored in a memory in the signal extractor according to the first embodiment of the present invention. (A) It is the frequency value of the peak at time T1. (B) It is the frequency value of the peak at time T2. (C) It is the frequency value of the peak at time TN.

FIG. 5 is a block diagram showing a target wave extraction method according to a second embodiment of the present invention. (A) The frequency distribution of the received signal at time T1 and the threshold of the signal level are shown. (B)
The frequency distribution of the received signal and the signal level threshold value at time T2 are shown. (C) The frequency distribution of the received signal at time TN and the threshold of the signal level are shown.

FIG. 6 is a block diagram showing a configuration of an unnecessary wave removing device according to a third embodiment of the present invention.

FIG. 7 is a diagram illustrating a target wave extraction method according to a third embodiment of the present invention. (A) A frequency distribution of the I component of the received signal at time T1. (B) The frequency distribution of the I component of the received signal at time T2. (C) The frequency distribution of the I component of the received signal at time TN.

FIG. 8 is a diagram illustrating a target wave extraction method according to a third embodiment of the present invention. (A) A frequency distribution of the Q component of the received signal at time T1. (B) A frequency distribution of the Q component of the received signal at time T2. (C) A frequency distribution of the Q component of the received signal at time TN.

FIG. 9 is data stored in a memory in the signal processor according to the third embodiment of the present invention. (A) The phase at each frequency at time T1. (B) The phase at each frequency at time T2. (C) The phase at each frequency at time TN.

FIG. 10 is a block diagram showing a configuration of an unnecessary wave removing device according to a fourth embodiment of the present invention.

FIG. 11 is a diagram showing a method of extracting an objective wave according to the fourth embodiment of the present invention.

FIG. 12 is a diagram when an array antenna is configured by using a plurality of radio wave monitoring devices according to a fourth embodiment of the present invention.

FIG. 13 is a block diagram showing a configuration of a conventional microwave detection device.

FIG. 14 is a diagram illustrating a general operation of microwave detection.

[Explanation of symbols]

1 antenna, 2 high frequency amplifier, 3 mixer, 4 intermediate frequency amplifier, 100 receiver,
200 unnecessary wave removing device, 201 AD converter, 2
Reference numeral 02 memory, 203 signal processor, 204 control device, 250 down converter, 251 filter, 252 fast Fourier transformer, 253 signal extractor, 254 memory, 256 modulation method detecting means, 257 waveform synthesizing means, 300 upper device.

Claims (4)

[Claims] 1. A converter for converting a received radio wave signal from a time domain to a frequency domain, and a frequency and a bandwidth in which at least one of the frequency, bandwidth and appearance time of a peak included in the output of the converter is preset. And a signal extractor that determines whether or not the appearance time matches, and outputs a determination result. 2. The radio wave monitoring device according to claim 1, wherein the signal extractor determines that a peak exists when a signal level higher than a preset value is measured. 3. A distribution means for distributing the received radio wave signal into an in-phase component and a quadrature component, a converter for converting the distributed in-phase component and quadrature component from the time domain to the frequency domain, and output from this converter. Phase detection means for comparing the in-phase component and the quadrature component to detect the phase of the received radio wave signal, the frequency of the peak included in the output of the converter, the bandwidth, the appearance time and the difference output from the phase detection means. At least one of the phases is a preset frequency, bandwidth, appearance time, and determines whether or not to match the differential phase determined from the modulation method, and a signal extractor for outputting the determination result, characterized in that Radio monitoring equipment. 4. The signal extractor comprises frequency distribution synthesizing means for synthesizing frequency distributions from preset modulation schemes and modulation speeds, scanning the frequency band of a received radio wave signal, and synthesizing the synthesized frequency distribution waveforms. 4. The radio wave monitoring device according to claim 3, wherein it is determined whether or not there is a peak that coincides with, and the higher-order device is notified of the coincident peak.